Elucidation of urinary metabolites of fluoxymesterone by liquid chromatography-tandem mass spectrometry and gas chromatography-mass spectrometry

✍ Scribed by Oscar J. Pozo; Wim Van Thuyne; Koen Deventer; Peter Van Eenoo; Frans T. Delbeke

• Publisher: John Wiley and Sons
• Year: 2008
• Tongue: English
• Weight: 340 KB
• Volume: 43
• Category: Article
• ISSN: 1076-5174
• DOI: 10.1002/jms.1343

✦ Synopsis

Abstract

The suitability of liquid chromatography tandem mass spectrometry (LC‐MS/MS) and gas chromatography mass spectrometry (GC‐MS) for the elucidation of fluoxymesterone metabolism has been evaluated. Electrospray ionization (ESI) and collision induced dissociation (CID) fragmentation in LC‐MS/MS and electron impact spectra (EI) in GC‐MS have been studied for fluoxymesterone and two commercially available metabolites. MS^n^ experiments and accurate mass measurements performed by an ion‐trap analyser and a QTOF instrument respectively have been used for the elucidation of the fragmentation pathway. The neutral loss scan of 20 Da (loss of HF) in LC‐MS/MS has been applied for the selective detection of fluoxymesterone metabolites. In a positive fluoxymesterone doping control sample, 9 different analytes have been detected including the parent compound. Seven of these metabolites were also confirmed by GC‐MS including 5 previously unreported metabolites. On the basis of the ionization, the CID fragmentation, the accurate mass of the product ions and the EI spectra of these analytes, a tentative elucidation as well as a proposal for the metabolic pathway of fluoxymesterone has been suggested. The presence of these compounds has also been confirmed by the analysis of five other positive fluoxymesterone urine samples. Copyright © 2007 John Wiley & Sons, Ltd.